Pathological gambling is becoming an increasing concern for the Spanish population. Governmental figures from 1989 show that in the Autonomic Region of Andalucia, with a population of 7 million inhabitants, more than three hundred billion pesetas (approximately UK pounds 1,500 million) were spent during 1988 gambling in casinos, slot machines and at bingo. These figures represent an increase of 15% over the figures of the previous year and suggest that gambling may have come a very important problem in Spain. This paper presents the first epidemiological study carried out in Spain on gambling and the estimated prevalence of pathological gambling in Seville, political capital of Andalucia. A sample of 598 individuals were interviewed with an adapted screening instrument. The results suggest that further epidemiological studies are required at a national level. They also indicate that preventive and treatment measures should also be taken urgently.